As an applying field of energy storage technique is enlarged to a cellular phone, a camcorder, a laptop PC and an electrical vehicle, efforts on studying and developing batteries have been increasingly concretized, and an electrochemical device receives the most attention in this aspect.
Particularly, according to the trend of electronic devices, efforts on developing a lithium secondary battery having small size, light weight and capable of charging and discharging in high capacity have been continued.
The lithium secondary battery is composed of a cathode and an anode, which include an electrode active material that may intercalate and deintercalate lithium ions, a separator disposed therebetween and an electrolyte as a delivering medium of the lithium ions.
Meanwhile, as the applying field of the lithium secondary battery is gradually enlarged, a battery including an organic polymer including an ionic side group, for example, an ‘ionomer’ compound in at least one element constituting the lithium secondary battery is known to maintain good performance in a severe environment such as high temperature or low temperature environment (see Patent Document 1).
That is, in the case in which a compound of an ionomer type is introduced in at least one element constituting the lithium secondary battery, an ion conductive layer may be formed on the surface of a constituting element or a gel type electrolyte may be formed, thereby realizing battery properties, which is normally difficult to obtain when using a liquid electrolyte.